Preheat the oven to 375 degrees F. Line a baking sheet with parchment paper or a silicone baking mat. Set aside.
In a medium mixing bowl, stir together the flour, baking powder, and salt. Set aside.
In a large mixing bowl, beat the butter, sugar, brown sugar, and ground cinnamon together until smooth and fluffy, about 1 minute. Add the eggs and vanilla and mix to combine, scraping the sides of the bowl as needed.
Add the dry ingredients to the wet ingredients in two additions, mixing until just combined after each addition.
Use a medium cookie scoop (or measuring spoon) to scoop the cookie dough into 2-tablespoon portions. Roll each scoop into a ball, place them 2 inches apart on the prepared baking sheet, and then gently flatten the balls so they are about 1/2-inch thick.
Bake for 8-10 minutes, or until the edges are golden brown and the middle of the cookie looks dry. Remove from the oven and cool on the baking sheet for a few minutes before transferring to a wire rack to cool completely. (The cookies are delicate, so be careful when moving them.)
Frosting
Once the cookies are cooled, make the frosting. In a medium mixing bowl, beat the cream cheese, butter, vanilla, and cinnamon until evenly combined. Beat in the powdered sugar 1 cup at a time until the frosting is smooth.
Transfer the frosting into a piping bag with a medium or large round tip. Starting in the center of the cookie, pipe the frosting in a spiral pattern to the outer edge. Repeat with the rest of the cookies and frosting. Dust the tops of the cookies with a little more ground cinnamon before serving.
Notes
If you don't have piping bags and tips, you can put the frosting into a large ziploc bag and cut one corner off. (The larger the hole, the wider the frosting swirls will be.)
Chill the frosted cookies in the fridge in a single layer for about 30 minutes until the frosting firms up. Then, you'll be able to stack the cookies on top of each other.